I saved the $100 and bought the i5 with a 512GB. You dont have to get the i7 in order to get the 256GB. I decided on the 512GB since its cheaper than the 480GB from OWC.
Actually it isnt.
You're paying $800 for the 512GB SSD upgrade.
From stock you pay an additional $300 for 256GB (from 128GB) and THEN pay another $500 to go from 256GB to 512GB.
All the while Apple keeps the memory you've already paid for.
Good job we love them, because not many companies could get away with this!